President Obama in his September 10 speech did not deliver a viable war-fighting strategy against ISIS. In fact, the president doesn’t seem to understand that ISIS is at war with the U.S.

The 18th century Prussian strategist General Carl von Clausewitz defined war as “an act of force to compel the enemy to do your will.” By that strategic definition, ISIS, the spawn of al Qaeda, has been at war with Americans for nearly two decades. Its modus operandi is terrorism, which is currently defined as “violence conducted against innocents to achieve a political objective.”

One of al Qaeda’s objectives even before 9/11 was to force Washington to withdraw from the Middle East by 2014. Al Qaeda achieved that goal in large part because its strategic objective coincided with the Obama administration’s disengagement policy. This left Iraq vulnerable to aggression by ISIS, whose leaders recently declared war on the United States. The beheading of two U.S. citizens makes clear ISIS’ proclivity for barbarism and terror.

The Obama administration’s ignorance of modern military history matches its lack of understanding of the Islamic State’s objectives. In fact, President Obama hasn’t even identified the enemy correctly. He insists on using the phrase “Islamic State in the Levant,” or “ISIL,” rather than the Islamic State in Iraq and Syria. Doing so implies failure in fighting the war in Iraq.

It has been 73 years since Congress last declared war. Since then, on occasion, American presidents have sought congressional approval for using military force. In August 1964, Congress passed the Gulf of Tonkin Resolution authorizing President Johnson to conduct military operations in Southeast Asia. Subsequently, North Vietnam responded to U.S. accusations that its treatment of captured American pilots violated the Geneva Convention by pointing out that because there was no declared state of war, American military action was illegal and the pilots therefore were “war criminals.” Hanoi also responded with a sound strategy to compel the United States to withdraw its forces, crush Saigon’s army, and unite all of Vietnam under a single communist system. Although “not at war” in Vietnam, the United States suffered 48,000 combat deaths.

Al Qaeda, far from “decimated”—as the Obama administration claims—has metastasized into a franchise of like-minded groups from Libya to Syria and Iraq where ISIS is entrenched and butchering almost at will. In this kind of war, to not win is to lose.

In his September 10 speech, President Obama still seems to believe that the threat posed by ISIS is “manageable.” What does that mean? Can barbarism be managed? How can the U.S. manage an evil that beheads innocents, that rapes and enslaves captive women, and that slaughters Iraqi prisoners of war? How can political leverage be exerted over a state with an expansionist ideology driven by a religious imperative demanding conversion or death for all unbelievers? The United States and its allies have dealt with state-sponsored barbarism in the past. Even before the United States declared war on December 8, 1941, President Roosevelt and British Prime Minister Winston Churchill understood the only acceptable conclusion would be the unconditional surrender of its enemies and the destruction of their regimes.

President Obama’s four points are nothing new. The first point merely states that he intends to intensify a minimal air campaign, which is tactical in its nature. The second point is that we will continue aiding the Iraqi Army, the Kurdish forces and increase our aid to Syrian rebels. All of these are ongoing operations. The third and fourth points merely reflect operations already in progress. Alluding to operations in Somalia and Yemen which have been modest but successful is an illusion. We have done no more than “manage” threats in those countries.

The Pentagon can bring decisive force to bear. Victory or defeat turns on strategy. Despite 13 years of fighting in Afghanistan and Iraq, combat-honed American military forces, armed with the world’s most advanced weaponry, can destroy ISIS.

In his September 10 speech, the president failed to rally American support. He failed to clearly articulate the threat and develop a strategy appropriate to the challenge of winning the war at hand. To win a war one must first recognize the true nature of the war and not try to turn it into some politically acceptable paradigm.

No amount of military force, bloodshed or heroism can overcome a flawed strategy. If the United States fails to regain the initiative and then destroy the Islamic State, it will lose this war. And the ramifications of that for the civilized world could be incalculable.

Dr. Earl Tilford is a military historian and fellow for the Middle East & terrorism with The Center for Vision & Values at Grove City College. He currently lives in Tuscaloosa, Alabama where he is writing a history of the University of Alabama in the 1960s. A retired Air Force intelligence officer, Dr. Tilford earned his PhD in American and European military history at George Washington University. From 1993 to 2001, he served as Director of Research at the U.S. Army’s Strategic Studies Institute. In 2001, he left Government service for a professorship at Grove City College, where he taught courses in military history, national security, and international and domestic terrorism and counter-terrorism.